Page 121 - Science Course 3 (Book 2)

Mo11-L3a: What is Absolute-Age Dating?

Let’s Begin Atoms

All atoms of a given element have the same number
Absolute Ages of Rocks of protons.

Scientists have been able to determine the absolute One proton; One proton;
ages of rocks and other objects since the beginning Zero neutrons One neutron
of the twentieth century, when radioactivity was
discovered.

Radioactivity is the release of energy from unstable
atoms.
Hydrogen Hydrogen – 2
Energy Nucleus Nucleus
One proton;
Two neutrons

Radiation

Radioactive Hydrogen – 3
Atom Nucleus
Particle

Isotopes are atoms of the same element that have
Key Concept different numbers of neutrons.
What is Absolute-Age Dating?
Stable isotopes do not change under normal
How is absolute age different from relative age? conditions.

Protium Deutrium

Tritium

Radioactive decay is
the process by which
an unstable element
naturally changes
into another element
that is stable.

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